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MaXyM
25-03-2018, 11:57
While going deeper and deeper into detailed preparation for league race I need a confidence about setting tire pressures.
I'm going to organize my doubts into questions:


What tire temperature the setup has to be configured for

always for cold one
for temperature shown in tires setup page (sometimes about 30* which is considered cold, sometimes prewarmed temp, ie 80*C for GT cars)


Related to #1: Considering car class with pre-warmed tires (GT3), does it matter in which session I'm configuring the setup? If the setup is prepared during practice or qualify (for GT3 those are pressures for cold tires), is such setup still valid for race where the race is starting with pre-warmed tires?
What temperature do I have to set pressures up for, in pit strategy:

for cold tire (the same values as in setup created during practice)
for pre-warmed tires if I'm changing tires during pitstop
for current temperature of tires if I'm not changing tired during pitstop




Speaking about tire page in setup. It shows a tire with 3 temperatures and with pressure. Is it useful for anything?
Especially values shown on this page are quite off. For example, for BMW M6 GT3@Imola, 26 July, when tire pressure is set to 1.38BAR, just before starting a race, setup shows 1.70BAR for 104*C for rolling start or 1.67BAR for standing start, which is even worse, because on practice I reached stable 1.80BAR for tire temperatures about 90-95*C.

Then I start a race and telemetry shows even different values. For example for standing start it shows 1.68BAR for 86*C. What is 104* shown in setup?
Right now I'm really confused.

Thanks in advance.

konji
25-03-2018, 12:28
From my experience tyre pressures seems to be quite random. Im unable to set it right and be sure that i will get pretested results in the race. What is completly random for me -> tyres behaviour after pitstop and tyres change. Sometimes changed tyres (soft slick to soft slick gt3 audi r8) seems to work waaaay better than original tyres i started race on, sometimes changed tyres works terribly (sliding on the ice, literally). And this is the same setup and the same strategy always.

hkraft300
25-03-2018, 13:27
1. If in practice you reach a stable pressure and the tire is in its operating range, then don’t worry about the race start. In 1 lap, whatever the automatic heating race start tire temp/pressure is, it will adjust according to your setup.
If your setup gives you 1.8 bar consistently, after the race start the tires will shift to it. Doesn’t matter if you start on automatic pre-warmed or cold tires.

2. Valid.

3. See 1. You are already setting your tire pressure (cold) such that it will eventually rest at ~1.8 bar. Same will happen during the race unless the conditions change.


. What is completly random for me -> tyres behaviour after pitstop and tyres change. Sometimes changed tyres (soft slick to soft slick gt3 audi r8) seems to work waaaay better than original tyres i started race on, sometimes changed tyres works terribly (sliding on the ice, literally).

It takes 5-8 laps for tires to settle. If you’re doing 3 lap stints to set your tire pressure, then they will be wrong st race start.

Also you have to save pit strategy tire pressures during the 2 minute race ready screen, or it won’t save and give you wrong pressure after pit stop.

MaXyM
25-03-2018, 14:24
OK. Thank you for clarification. So, doesn't matter when and where I set pressures, all of them settings refers to so-called cold tire. So, even if I don't change tires, I have to setup the same pressures as in initial setup (considering it's perfect setup to me).
I can feel I miss an option to request tire pressure change, to desired value (not using prepared strategy).


Also you have to save pit strategy tire pressures during the 2 minute race ready screen, or it won’t save and give you wrong pressure after pit stop.

Do you mean "activate strategy" or literally saving it again?

konji
25-03-2018, 14:38
We are doing 1h/1,5h/2h races. I always adjust my setups in min. 0,5h or 1h practices on same dedicated server and same conditions like in races. I always resave setup before race in 2 min window and check gear ratios becouse i have it bugged almost everytime before race. I always reselect strategy before race in 2 min window but i never resave it. Should I?

hkraft300
25-03-2018, 14:45
OK. Thank you for clarification. So, doesn't matter when and where I set pressures, all of them settings refers to so-called cold tire. So, even if I don't change tires, I have to setup the same pressures as in initial setup (considering it's perfect setup to me).
I can feel I miss an option to request tire pressure change, to desired value (not using prepared strategy).

Oh now I see what you mean. In setup menu, you’re adjusting the cold tire pressures (except LMP1 and FA/X?). Which you already know. Then when the tire and brakes heat up on track, you get “hot” pressure.



Do you mean "activate strategy" or literally saving it again?

Activate strategy, then edit the tire pressures to match your setup, then save.
During the pre-race ready screen.
Then when you pit for tire change, you will get correct tire pressures.

MaXyM
25-03-2018, 14:56
Yes, I know I have to prepare strategy, by changing and saving values. I usually do it during preparation hours before the race. Not just at beginning of the race session. You mentioned the need of "saving" strategy after activating it, so it sounds like activating already prepared strategy is not enough. Do I understand it incorrectly or we are talking about an unreported bug?

Why for LMP1 it's not for cold tire? Just asking because for GT3 you can work with setup during practice and qualify sessions when tires are cold. But if you open setup in race session (while cars are waiting on a grid), tires are already warmed up to about 80*C. I'm still assuming, pressures in this case are being set up for cold tires temperature. Not for current one.

hkraft300
25-03-2018, 15:34
Yes, I know I have to prepare strategy, by changing and saving values. I usually do it during preparation hours before the race. Not just at beginning of the race session. You mentioned the need of "saving" strategy after activating it, so it sounds like activating already prepared strategy is not enough. Do I understand it incorrectly or we are talking about an unreported bug?

Only for the tire pressures. Activate, edit pressures, save.*


Why for LMP1 it's not for cold tire?

Because it gets warm tires, at 80c. So your “cold” pressure is higher than GT3 tires in setup menu, but procedure is the same.


Just asking because for GT3 you can work with setup during practice and qualify sessions when tires are cold. But if you open setup in race session (while cars are waiting on a grid), tires are already warmed up to about 80*C. I'm still assuming, pressures in this case are being set up for cold tires temperature. Not for current one.

Yes, for cold tires in GT3.

* this May only be a pre-patch 4 issue, but better safe than sorry.

Invincible
26-03-2018, 08:42
Especially values shown on this page are quite off. For example, for BMW M6 GT3@Imola, 26 July, when tire pressure is set to 1.38BAR, just before starting a race, setup shows 1.70BAR for 104*C for rolling start or 1.67BAR for standing start, which is even worse, because on practice I reached stable 1.80BAR for tire temperatures about 90-95*C.


The differences between practice and race start most likely come from brake temperatures. From the looks of it, you were running your brakes pretty hot in the practice.

iggy
26-03-2018, 12:41
The whole tire pressure for pit stop strategy is very odd...

For starters, that unit of measure is always in BAR, even when you have things setup for imperial (PSI) , everywhere else will read in PSI, but for some reason they don't give those of us who use imperial measurements the ability to set pressure in pit strategy in PSI.

The next odd thing is, that there's no way that I'm aware of to quickly copy the pressure from normal setup config, to the pressure needed to put into the race strategy. Seems there should just be a way to say... 'use the same pressure that I've configured in my setup' or maybe a way to say take 0.2 PSI out of the left rear, etc...

Bealdor
26-03-2018, 12:42
The next odd thing is, that there's no way that I'm aware of to quickly copy the pressure from normal setup config, to the pressure needed to put into the race strategy. Seems there should just be a way to say... 'use the same pressure that I've configured in my setup' or maybe a way to say take 0.2 PSI out of the left rear, etc...

Reset your pit strategy to defaults (or create a new one) and it'll automatically take the pressures from your currently loaded car setup.

cpcdem
26-03-2018, 13:29
Reset your pit strategy to defaults (or create a new one) and it'll automatically take the pressures from your currently loaded car setup.

Yes, but that means that every time you adjust pressures in the setup, you must again reset pit strategy. Or have I not understood how it works? I think that an option "same as in setup" is really needed.

AbeWoz
26-03-2018, 13:32
Yes, but that means that every time you adjust pressures in the setup, you must again reset pit strategy. Or have I not understood how it works? I think that an option "same as in setup" is really needed.

correct. For that reason, I do not set pit strats until i'm finished with my car setup.